Stabilisation/solidification (S/S) is a civil engineering based ground remediation technique that involves the controlled addition and mixing of cementitious powders with contaminated soil to render a wide variety of contaminant types immobile and virtually non-leachable.
The addition of cement and lime to soils introduces a combination of the two separate processes of stabilisation (the production of more chemically stable constituents) and solidification (the imparting of physical/dimensional stability to contain contaminants in a solid product and reduce access by external agents, such as air or rainfall). The two processes work together and the chemical and physical changes can be optimised - through careful selection of binder materials and minor additives - to achieve the desired remedial objectives. Although not totally removed or destroyed, S/S removes pathways between contaminants and potential receptors, thereby eradicating associated risk.
At the same time as achieving the remedial objectives the engineering properties of the soil are improved, thereby facilitating the development of the site.
Further information is in the publication The Essential Guide to the Remediation of Brownfield Land:
This document provides guidance on the use of Stabilisation/Solidification (S/S) for the remediation of land affected by contamination, as commonly found on brownfield land or derelict sites.
The process is based on well understood science.
It can be used on a wide range of different contaminants and can be tailored to meet the requirements of the site specific risk assessment.
It has a proven track record in projects worldwide.
It provides an improvement to the physical characteristics of the ground in addition to managing the contamination issues.
It requires conventional ground engineering equipment and ties in well with other site construction activities.
It offers clearly defined cost and project programme benefits.
It can avoid disposal of contaminated soils to landfill, drastically reduce the need to import fill and reduce vehicular movements to and from site.